Lourenswalsite Locality: Diamond Jo Quarry, Magnet Cove, Hot Spring Co., Arkansas, USA Light brownish rosette of Lourenswalsite, field of view 2,5 mm. Specimen and photo Leon Hupperichs. — Photo: Leon Hupperichs · CC BY-SA 3.0
Lourenswalsite
Lourenswalsite is an IMA-recognized mineral species in the silicate class, with the chemical formula (K,Ba)₂Ti₄(Si,Al)₆O₁₄(OH)₁₂.
It crystallizes in the hexagonal crystal system.
Key properties: specific gravity 3.17; Pearly to dull luster; optically biaxial.
IMA symbol Lrw, IMA status: approved, named in 1987.
A secondary mineral developed during weathering, in vugs and miarolitic cavities in a titaniferous nepheline syenite.
It is found associated with Labuntsovite, delindeite, pectolite, barite, pyroxene, titanite, sphalerite, potassic feldspar.
In honor of Dr. Lourens Wals, mineral collector of Turnhout, Belgium.